Phase average visualization of a finite cylinder wake as predicted by large eddy simulation

Abstract

The current paper reports a large eddy simulation (LES) of turbulent flow over a finite-height square cylinder mounted normal to a ground plane. The cylinder aspect ratio is AR = 3 and the Reynolds number based on the cylinder width and inlet velocity is Re = 500. The flow field is complex, since the flow over the top of the cylinder interacts with the flow along the ground plane to create a complicated wake structure. The wake is characterized by a velocity field that changes rapidly in both direction and magnitude. Phase averaging based on the Strouhal number reveals a wake structure with quasi-periodic features that is much different from the structure suggested by the mean vorticity field.